I’ve never really understood how something travelling faster than teh speed of sound causes a sonic boom.
Secondary, like when man first broker the sound barrier, did the scientists *know* a sonic boom would occur, or was it a surprise and they all were like “WTF was that, did we just break something”?
Thirdly, is a sonic boom guaranteed when something breaks the sound barrier, or do they sometimes not happen?
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You fling your arms forward while screaming “sonic boom!” Do this repeatedly to confuse and annoy your opponent
Imagine if you are listening to a radio. It is playing just a little 5second snippet of music.
You take 5 seconds to listen to that music, and it is at its normal volume.
Now, imagine someone throws it at you at the speed of sound. They miss, so it goes really close to your ear.
The radio is moving at the speed of sound, so *you can’t hear it until the radio passes you* because the sound is not faster than the radio, and so the sound doesn’t extend further forward than the radio.
You therefore hear all 5 seconds of the music *at once*. You hear every single sound in the sound at the same time, because none of them can reach you earlier, because the source of the music was moving with the sound it was generating.
Instead of having 5 seconds to slowly absorb the sound energy into your ears, all the energy of 5 seconds of music gets put into your eardrum in an instant.
That’s loud!
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Now, instead of music, the sound here is perhaps the roar of the jet engine, or the turbulent sound of wind-drag.
That sound stacks on top of each other, and it is loud because you hear all the osund at once.
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Note that the sound is still limited because you hear a combination of the sounds, scaled with distance at the time the sound was generated.
Like imagine that radio again.
I said 5 seconds of music. That means that the radio started over 1500m (like a mile or so) away from you!
To make the maths easy I’ll ay the speed of sound is 300m/s (it is a bit more than that, but this round number is easier to work with).
We don’t get much from:
* the 1st second of music while the radio 1500m-1200m away.
* the 2nd second of music while the radio is 1200m-900m away.
* the 3rd second of music from 900-600m away.
* the 4th second of music from 600-300m away.
Even mosto f the 5th second of music will be inaudible, because the radio is so far away for most of it.
You are really only hearing the noise from the last fraction of a second. Like a radio might be audible from like 100m away or so, so like the last 1/3rd of a second.
Still, you normally hear continuous infinitesmal fractions of sound, so 1/3rd of a second all at once is still loud. (And we add the turbulent noise of the object flying past.)
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